Conventionally, there is known an internal magnet type speaker device including a magnetic circuit including a plate-shaped magnet, a planar plate and a pot type yoke, and a vibrating system including a diaphragm, a damper, a connecting member made of a resin material, a voice coil, a voice coil bobbin and a frame.
In such the speaker device, the connecting member is supported by the damper and is mounted to the voice coil bobbin, and movably holds the voice coil bobbin. An inner peripheral edge portion of the damper is mounted to an outer peripheral wall of the connecting member via an adhesive.
However, in the above-mentioned speaker device, the damper is fixed to the connecting member only by the adhesive applied between the outer peripheral wall of the connecting member and the damper itself. Thus, adhesion strength of the damper and the connecting member is small, and bonding strength of the damper and the connecting member is also small. Therefore, at the time of driving the speaker device, the damper easily peels off the connecting member.
There is known a speaker device for improving adhesion strength of a damper and a voice coil (see Japanese Patent Application Laid-Open under No. 9-224298, for example). According to the document, an inner peripheral edge portion of the damper is formed in a taper shape, and an adhesive sump is formed by the taper shape and the voice coil, thereby improving the adhesion strength of the damper and the voice coil.
There is also known a speaker device in which a damper does not peel off even at the time of a large magnitude movement of a vibrating system (see Japanese Patent Application Laid-Open under No. 11-32390, for example). According to the document, a flat portion is formed at an internal diameter portion of the damper, and the flat portion and the lower edge of the voice coil are fixed by the adhesive. Thereby, the adhesion strength of the damper and the voice coil is maintained, and it is prevented that the damper peels off even at the time of the large magnitude movement of the vibrating system.